/*
*    Qizx/open 3.0 beta
*
* This code is the open-source version of Qizx.
* Copyright (C) 2004-2009 Axyana Software -- All rights reserved.
*
* The contents of this file are subject to the Mozilla Public License 
*  Version 1.1 (the "License"); you may not use this file except in 
*  compliance with the License. You may obtain a copy of the License at
*  http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
*  WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
*  for the specific language governing rights and limitations under the
*  License.
*
* The Initial Developer of the Original Code is Xavier Franc - Axyana Software.
*
*/
using System;
using EvaluationException = System.Qizx.Api.EvaluationException;
namespace System.Qizx.XQuery.Impl
{
	
	/// <summary> [Internal use] Thrown when a empty Value is encountered in a context that
	/// cannot handle it. Can be caught be enclosing expressions that accept empty
	/// sequences.
	/// </summary>
	[Serializable]
	public class EmptyException:EvaluationException
	{
		public EmptyException(string reason):base(reason)
		{
		}
		
		/// <summary> Unique instance.
		/// <p>
		/// Throwing a statically built exception is perfectly possible in Java.
		/// This saves the time needed to copy the call stack into the exception, at
		/// the cost of a meaningless printStackTrace(). But we dont care here,
		/// because this is meant to simplify the handling of optionally empty
		/// arguments.
		/// </summary>
		public static EmptyException instance()
		{
			return instance_Renamed_Field;
			// return new EmptyException("unexpected empty sequence");
		}
		
		/// <summary> Unique instance.</summary>
		public static EmptyException instance_Renamed_Field = new EmptyException("unexpected empty sequence");
	}
}